Pallets are used to support goods above the floor for shipping and storage. Many pallets are now plastic. A pallet includes at least one deck for supporting the goods. A plurality of columns extend downwardly from the deck to support the deck above the floor. Openings between the columns receive forks of a forklift or a pallet jack. Some pallets are nestable, that is, the columns of one pallet are received through openings in the deck and into the columns of another pallet. This reduces the stacking height of the pallets when the pallets are empty.
Some pallets have nine columns, including four corner columns, side or end columns between the corner columns on each side or end of the pallet, and a center column. Each tine of a fork is inserted on either side of the side or end columns. However, some pallets, such as half pallets, do not include side or end columns. Therefore, more care is required to ensure that the fork is substantially centered on the pallet deck prior to lifting the pallet off the floor.
The columns of the pallets are often subject to high impact from the forks. It has been proposed to spray structural foam into the hollow plastic columns in order to increase the impact resistance of the columns. However, this makes it very difficult to recycle the plastic pallet, as the structural foam cannot be recycled with the pallet.